From patchwork Fri Aug 8 14:12:47 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Klug X-Patchwork-Id: 24080 Return-Path: X-Original-To: parsemail@patchwork.libcamera.org Delivered-To: parsemail@patchwork.libcamera.org Received: from lancelot.ideasonboard.com (lancelot.ideasonboard.com [92.243.16.209]) by patchwork.libcamera.org (Postfix) with ESMTPS id 65CE8BDCC1 for ; Fri, 8 Aug 2025 14:14:12 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id 1EF2069230; Fri, 8 Aug 2025 16:14:12 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="guKc8LFl"; dkim-atps=neutral Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 20F0C6921E for ; Fri, 8 Aug 2025 16:14:10 +0200 (CEST) Received: from ideasonboard.com (unknown [IPv6:2a00:6020:448c:6c00:3ea1:35ac:90da:a221]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id 2C936208E; Fri, 8 Aug 2025 16:13:20 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1754662400; bh=AZBECBfp5wAEJjuKXVy2zSaRSaqp6qqt7J1e6gBu4I4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=guKc8LFlRyIuZx/Pn0q7LxavfC6NkocyGIlgQHGVa56tFtVAc/Q2rTTthqPdbwal7 5uh89AkrI5nIenhmch1E9dL96HAiocCplsPHg3SjRxbyA2C5PP7FrfCK2QWyl2gvin kGOZn83TetXUUIcZZuoQF30Kd/WvFqYYwG9WR/Jw= From: Stefan Klug To: libcamera-devel@lists.libcamera.org Cc: Stefan Klug Subject: [PATCH v2 09/16] ipa: rkisp1: agc: Add correction for exposure quantization Date: Fri, 8 Aug 2025 16:12:47 +0200 Message-ID: <20250808141315.413839-10-stefan.klug@ideasonboard.com> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250808141315.413839-1-stefan.klug@ideasonboard.com> References: <20250808141315.413839-1-stefan.klug@ideasonboard.com> MIME-Version: 1.0 X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libcamera-devel-bounces@lists.libcamera.org Sender: "libcamera-devel" There are several occations where quantization can lead to visible effects. In WDR mode it can happen that exposure times get set to very low values (Sometimes 2-3 lines). This intentionally introduced underexposure is corrected by the GWDR module. As exposure time is quantized by lines, the smallest possible change in exposure time now results in a quite visible change in perceived brightness. Sometimes the possible gain steps are also quite large leading to visible jumps if e.g. if the exposure time is fixed. Mitigate that by applying a global gain to account for the error introduced by the exposure quantization. ToDo: This needs perfect frame synchronous control of the sensor to work properly which is not guaranteed in all cases. It still improves the behavior with the current regulation and can easily be skipped, when there is no compress algorithm. Signed-off-by: Stefan Klug Reviewed-by: Kieran Bingham Reviewed-by: Daniel Scally --- src/ipa/rkisp1/algorithms/agc.cpp | 24 +++++++++++++++++++++--- src/ipa/rkisp1/ipa_context.h | 2 ++ 2 files changed, 23 insertions(+), 3 deletions(-) diff --git a/src/ipa/rkisp1/algorithms/agc.cpp b/src/ipa/rkisp1/algorithms/agc.cpp index 0a29326841fb..d34c041f9fe1 100644 --- a/src/ipa/rkisp1/algorithms/agc.cpp +++ b/src/ipa/rkisp1/algorithms/agc.cpp @@ -199,6 +199,9 @@ int Agc::configure(IPAContext &context, const IPACameraSensorInfo &configInfo) context.configuration.agc.measureWindow.h_size = configInfo.outputSize.width; context.configuration.agc.measureWindow.v_size = configInfo.outputSize.height; + AgcMeanLuminance::configure(context.configuration.sensor.lineDuration, + context.camHelper.get()); + setLimits(context.configuration.sensor.minExposureTime, context.configuration.sensor.maxExposureTime, context.configuration.sensor.minAnalogueGain, @@ -283,6 +286,10 @@ void Agc::queueRequest(IPAContext &context, if (!frameContext.agc.autoGainEnabled) frameContext.agc.gain = agc.manual.gain; + if (!frameContext.agc.autoExposureEnabled && + !frameContext.agc.autoGainEnabled) + frameContext.agc.quantizationGain = 1.0; + const auto &meteringMode = controls.get(controls::AeMeteringMode); if (meteringMode) { frameContext.agc.updateMetering = agc.meteringMode != *meteringMode; @@ -336,12 +343,17 @@ void Agc::prepare(IPAContext &context, const uint32_t frame, { uint32_t activeAutoExposure = context.activeState.agc.automatic.exposure; double activeAutoGain = context.activeState.agc.automatic.gain; + double activeAutoQGain = context.activeState.agc.automatic.quantizationGain; /* Populate exposure and gain in auto mode */ - if (frameContext.agc.autoExposureEnabled) + if (frameContext.agc.autoExposureEnabled) { frameContext.agc.exposure = activeAutoExposure; - if (frameContext.agc.autoGainEnabled) + frameContext.agc.quantizationGain = activeAutoQGain; + } + if (frameContext.agc.autoGainEnabled) { frameContext.agc.gain = activeAutoGain; + frameContext.agc.quantizationGain = activeAutoQGain; + } /* * Populate manual exposure and gain from the active auto values when @@ -354,6 +366,12 @@ void Agc::prepare(IPAContext &context, const uint32_t frame, if (!frameContext.agc.autoGainEnabled && frameContext.agc.autoGainModeChange) { context.activeState.agc.manual.gain = activeAutoGain; frameContext.agc.gain = activeAutoGain; + frameContext.agc.quantizationGain = activeAutoQGain; + } + + if (context.activeState.compress.supported) { + frameContext.compress.enable = true; + frameContext.compress.gain = frameContext.agc.quantizationGain; } if (frame > 0 && !frameContext.agc.updateMetering) @@ -582,7 +600,7 @@ void Agc::process(IPAContext &context, [[maybe_unused]] const uint32_t frame, /* Update the estimated exposure and gain. */ activeState.agc.automatic.exposure = newExposureTime / lineDuration; activeState.agc.automatic.gain = aGain; - + activeState.agc.automatic.quantizationGain = qGain; /* * Expand the target frame duration so that we do not run faster than * the minimum frame duration when we have short exposures. diff --git a/src/ipa/rkisp1/ipa_context.h b/src/ipa/rkisp1/ipa_context.h index 37a74215ce19..362ab2fda5fe 100644 --- a/src/ipa/rkisp1/ipa_context.h +++ b/src/ipa/rkisp1/ipa_context.h @@ -77,6 +77,7 @@ struct IPAActiveState { struct { uint32_t exposure; double gain; + double quantizationGain; } automatic; bool autoExposureEnabled; @@ -135,6 +136,7 @@ struct IPAFrameContext : public FrameContext { uint32_t exposure; double gain; double exposureValue; + double quantizationGain; uint32_t vblank; bool autoExposureEnabled; bool autoGainEnabled;